> >> Results of the tests revealed that the SGI Altix 330 using shared
> >> memory and unmatched I/O throughput achieved superior
> >> performance and ran faster than twice the number of cores in
> >> comparable AMD dual core Opteron-based systems.
well, it's a marketing paper: it's not in SGI's interest
to explore the whole vast, many-dimensional configuration space
to find the absolute best way to configure Opteron systems.
there's no doubt It2's run some code very well, and that SGI's
NUMAflex is a very nice interconnect.
but any honest reader must wonder:
- what would the results be for 8 processors? (that is,
higher-clocked Opterons, and not dual-core to avoid memory
contention.)
- what are the relative prices of the systems tested?
- was the Opteron configured with 8 banks of PC3200?
- why was sles9 used rather than sles10?
- why was gcc 3.3.3 used rather than 4.x or even 3.4.5?
- is mpich-1.2.7-ch_shmem really an optimal choice?
- which version of PGI was used on opterons? switches?
- for the Opteron benchmarks compiled with Intel compilers,
was it running actual SSE3 codepaths, or defaulting to PIII?
- is Intel LAPACK/MKL better or worse on Opterons than ACML/etc?
regards, mark hahn.